Powers of Negative Numbers: Adding parentheses in the correct place

Examples with solutions for Powers of Negative Numbers: Adding parentheses in the correct place

Exercise #1

9= 9=

Video Solution

Step-by-Step Solution

To solve this problem, we need to evaluate expressions by applying the rules of exponents and the effects of parentheses on negative numbers:

  • (3)2(-3)^2: When a negative number is squared, the result is positive. So, (3)2(-3)^2 means 3×3=9-3 \times -3 = 9.
  • (3)2-(-3)^2: This means 1×(3×3)-1 \times (-3 \times -3) because squaring a number negates the negative sign inside parentheses, resulting in 9-9.
  • (3)2-(3)^2: This equals 1×(3×3)=9-1 \times (3 \times 3) = -9, as the negative sign is outside the squared value.
  • 3-3: This is simply 3-3.

Only (3)2(-3)^2 equals 9, confirming it as the correct expression required by the problem.

Therefore, the solution to the problem is (3)2 (-3)^2 .

Answer

(3)2 (-3)^2

Exercise #2

64= 64=

Video Solution

Step-by-Step Solution

To solve this problem and express 64 as a power involving a negative number, we will follow these steps:

  • Step 1: Recognize that we need to represent 64 using a base number squared. Since 64 is a perfect square, let's consider negative integers whose square equals 64.
  • Step 2: The principal positive square root of 64 is 8. However, we are tasked with finding a negative number such that its square is 64.
  • Step 3: If we have a negative integer, (8)(-8), and square it, we have: (8)2=(8)×(8)=64(-8)^2 = (-8) \times (-8) = 64.
  • Step 4: Compare this with the expression (8)2-(8)^2, which results in 64-64 because the square applies only to 8, and the negative sign flips the result.

Therefore, the correct expression representing 64 with a negative base is (8)2(-8)^2, and among the answer choices provided, choice 1 is the correct one.

Answer

(8)2 (-8)^2

Exercise #3

8= 8=

Video Solution

Step-by-Step Solution

To solve this problem, let's evaluate both given expressions to determine which results in 8.

  • Step 1: Evaluate (2)3(-2)^3:
    (2)3=(2)×(2)×(2)(-2)^3 = (-2) \times (-2) \times (-2).
    Multiplying across: (2)×(2)=4(-2) \times (-2) = 4, and then 4×(2)=84 \times (-2) = -8.
    Thus, (2)3=8(-2)^3 = -8.
  • Step 2: Evaluate (2)3-(-2)^3:
    First, calculate (2)3(-2)^3 again: We already know (2)3=8(-2)^3 = -8.
    Now, apply the negative sign: (8)=8-(-8) = 8.

Therefore, the expression that equals 88 is (2)3-(-2)^3.

Thus, the correct expression that evaluates to 8 is (2)3-(-2)^3.

Answer

(2)3 -(-2)^3

Exercise #4

36= 36=

Video Solution

Step-by-Step Solution

To determine which expression equals 36, we need to consider how squaring works with negative numbers:
Step 1: Consider the expression (6)2(-6)^2. This means that we take -6 and multiply it by itself:
(6)×(6)=36(-6) \times (-6) = 36

Step 2: Consider the expression (6)2-(6)^2. Here, the square acts only on 6, not on the negative sign in front because of the absence of parentheses around -6:
(6×6)=36-(6 \times 6) = -36

Therefore, the expression (6)2(-6)^2 correctly equals 36.

The correct choice that satisfies 36= 36 = is (6)2(-6)^2.

Answer

(6)2 (-6)^2

Exercise #5

16= -16=

Video Solution

Step-by-Step Solution

To solve this problem, we'll need to carefully consider the placement of parentheses and the order of operations when dealing with negative numbers and exponentiation:

  • Step 1: Examine the given expression (4)2(-4)^2. This indicates squaring the entire negative four, which results in 1616.
  • Step 2: Now, examine (4)2-(-4)^2 paying close attention to the negative sign in front. (4)2(-4)^2 again results in 1616, but placing a minus before it changes its sign to 16-16.

Let's analyze each possible choice:

  • For choice 1: The expression is (4)2-(-4)^2. Calculating (4)2(-4)^2 gives 1616, and applying the negative sign outside results in the expression value of 16-16.
  • For choice 2: The expression is (4)2(-4)^2, calculated to give 1616.

Therefore, the expression that correctly equals 16-16 is choice 1, represented by (4)2-(-4)^2.

The correct answer is choice 1: (4)2-(-4)^2.

Answer

(4)2 -(-4)^2

Exercise #6

25= -25=

Video Solution

Step-by-Step Solution

To solve this problem, we'll evaluate each expression step by step:

  • Option a: (5)2(-5)^2
    This implies that we first compute (5)×(5)(-5) \times (-5) which equals 2525.

  • Option b: (5)2-(-5)^2
    First, find (5)2=25( -5)^2 = 25 . Then, apply the negative sign, resulting in 25-25.

  • Option c: (5)2-(5)^2
    First, find (5)2=25(5)^2 = 25. Then, apply the negative sign, resulting in 25-25.

Options b and c both evaluate to 25-25. Therefore, the correct answer is option d: "Answers b and c".

Answer

Answers b and c

Exercise #7

100= -100=

Video Solution

Step-by-Step Solution

To solve this problem, follow these steps:

  • Step 1: Identify that the problem involves finding a mathematical expression that equals 100-100.
  • Step 2: Consider how negative powers and negative bases interact with parentheses.
  • Step 3: Evaluate each choice using the properties of powers.

Now, let's evaluate each choice:

Choice 1: (1)100 (-1)^{100}
Computing: (1)100(-1)^{100} equals 11, since 100100 is even and any even power of 1-1 results in 11. Therefore, this choice cannot be 100-100.

Choice 2: (10)2 (-10)^2
Computing: (10)2(-10)^2 equals 100100, as squaring a negative number results in a positive number. Thus, this choice cannot be 100-100.

Choice 3: (10)2 -(-10)^2
Computing: (10)2-(-10)^2 means first computing (10)2(-10)^2, which is 100100, and then applying the negative sign resulting in 100-100. Therefore, this correctly matches 100-100.

Choice 4: 1100 1^{100}
Computing: 11001^{100} is 11, as any number raised to any power remains itself when the base is 11. Thus, it cannot equal 100-100.

Therefore, the correct choice is (10)2 -(-10)^2 , as it evaluates directly to 100-100.

Answer

(10)2 -(-10)^2

Exercise #8

49= 49=

Video Solution

Answer

(7)2 (-7)^2

Exercise #9

81= 81=

Video Solution

Answer

((3)2)2 ((-3)^2)^2

Exercise #10

16= -16=

Video Solution

Answer

(22)2 -(2^2)^2